Search bioRxiv⌕ Search

Biology subjects

Lopez-Bao, J. V.

Publications and source records attributed to Lopez-Bao, J. V..

3 recordsLinked to original sources

Population-specific drivers of reproductive phenology in a widespread large carnivore, the gray wolf

Animals often rely on cues from the environment to time reproduction with optimal conditions. However, for most species, which environmental cues are used and how their use varies across a species distribution remains poorly understood. The gray wolf (Canis lupus) is found across a broad latitudinal range (12{degrees}N to 83{degrees}N) and diverse natural habitats, making them an ideal study species to explore these questions. Using 1,261 estimated birth dates of wild and captive wolves across their global range, we investigated how environmental variables influence reproductive phenology in this widespread large carnivore. Birth dates for wild wolves ranged from November 22nd for Indian wolves (18{degrees}N) to June 15th for Arctic wolves (80{degrees}N). The best predictor of timing of birth was increasing daylength during the mating season, followed by precipitation variability during the year. The timing of birth in captive wolves was highly similar to wild wolves at same latitudes, suggesting they use similar environmental cues to time reproduction. Near the equator where photoperiod is more stable, wolves remained seasonal and likely use climatic cues to time reproduction. Our work reveals populations may use different environmental cues to time reproduction, a characteristic that likely facilitates adaptation to diverse environments.

ecology↗

The spatial distribution and temporal trends of livestock damages caused by wolves in Europe

Wolf populations are recovering and expanding across Europe, causing conflicts with livestock owners. To mitigate these conflicts and reduce livestock damages, authorities spend considerable resources to compensate damages, support damage prevention measures, and manage wolf populations. However, the effectiveness of these measures remains largely unknown, especially at larger geographic scales. Here we compiled incident-based livestock damage data across 21 countries for the years 2018, 2019 and 2020, during which 39,262 wolf-caused incidents were reported from 470 administrative regions. We found substantial regional variation in all aspects of the data, including the primary target species, the density of damages, their seasonal distribution, and their temporal trend. More than half of the variation in damage densities across regions is explained by the area of extensively cultivated habitats occupied by wolves and namely natural grasslands and broad-leaved forests. Regional variation in husbandry practices and damage prevention, while difficult to quantify at a continental scale, appear important factors to further modulate these incidents. As illustrated with detailed data from Germany, for instance, the relationship between the number of wolf units and damages is diminishing over time, suggesting some adaptation of livestock owners and local authorities to their presence, for example by increasing prevention efforts. As we argue, temporal trends of damage incidents, which are robust to variation in data collection across regions, are thus informative about the local intensity of the wolf-human conflict. We estimated increasing trends for the majority of regions, reflecting the current expansion of wolves across the continent. Nonetheless, many of these increases were moderate and for more than one third of all regions, trends were negative despite growing wolf populations, thus indicating that wolf-livestock conflicts can be successfully mitigated with proper management.

ecology↗

The contribution of the European LIFE program to mitigate damages caused by large carnivores in Europe

Governments around the world invest considerable resources to reduce damages caused by large carnivores on human property. To use these investments more efficiently and effectively, we need to understand which interventions successfully prevent such damages and which do not. In the European Union, the LIFE program represents by far the largest financial instrument to help EU Member States with the implementation of conservation activities, including mitigation of damages caused by large carnivores. However, we currently lack information about the effectiveness of this funding program in reducing carnivore damages. We reviewed 135 LIFE projects dealing with large carnivores between 1992 and 2019 to provide an overview of the use of damage prevention methods and evaluate their functional and perceived effectiveness. Methods evaluated ranged from non-lethal and lethal interventions, to information dissemination and compensation schemes. The largest number of the projects was focused on grey wolf (Canis lupus) and brown bears (Ursus arctos) in the Mediterranean countries and in Romania. Electric fences were reported as the most successful method for reducing damages by large carnivores, and most of the non-lethal methods used showed at least moderate effectiveness. However, standards of measuring and reporting effectiveness were in general relatively low, which limits our ability to measure actual impact. Therefore we urge project managers and evaluators to improve these standards, as well as the dissemination of the project results. We provide a list of recommendations for improving measuring and reporting success of implemented interventions for the benefit of future projects aimed to reduce damages caused by wildlife. Article impact statementElectric fences were reported as the most effective method to prevent large-carnivore damages and are recommended for future use.

zoology↗